One approach to provide additional computing power has been to utilize distributed computer environments. This approach enables several computers to collaboratively perform computational tasks within a reduced amount of time. Generally, the divide and conquer approach provided by such parallel computing approaches enables utilization of available personal computers, rather than purchasing of a high performance, server-based computer system for performing the computationally intensive tasks.
Distributed computing has generally, however, been applied to performing purely computational tasks and not to synchronized capture and/or processing of signals, especially audio/video signals (and data streams). Signal processing of audio/video signals (and data streams) are generally very sensitive to even very small differences in sampling rates (e.g., clock skew), jitter, and delays. Therefore, precise synchronization is very critical for high quality input/output processing, as well as for real-time performance and in general, robustness and reliability issues. But, precise capture and synchronized inputs are not guaranteed on current platforms.
For example, on the same personal computer (PC) platform, problems can arise when several input/output (I/O) devices are used to capture audio and visual information from video camera(s) and microphone(s). Due to the fact that the different I/O devices will be triggered by separate oscillators, resulting audio samples and video frames will not be aligned on an absolute time line (thus inducing some relative offsets). Moreover, due to differences in the oscillators' frequencies, audio and/or visual data will drift away across multiple channels/streams over time. Instabilities in the oscillators' frequencies will also not be perfectly correlated between each other.
Similarly, in the case of multiple PC platforms audio and visual I/O devices will not be synchronized in time scale inducing some relative offsets and data samples to drift relative to each other. The extent of the relative offset, drift, and jitter on the existing platforms depends on many hardware and software parameters and can be very significant, sometimes causing total degradation of the processed signals (from the non-synchronized input streams). Such drifts, delays, and jitters can cause significant performance degradation for instance for array signal processing algorithms.
For example, in an acoustic beam former with 10 centimeter (cm) spacing between microphones, an error of only 0.01 percent in time can cause error of 20 degrees in the beam direction. Due to this fact, current implementations of audio array process algorithms may rely on dedicated circuitry for the synchronization between multiple I/O channels. Unfortunately, implementing such an approach with existing PC platforms would require a major overhaul of the current hardware utilized by the PC platforms. Therefore, there remains a need to overcome one or more of the limitations in the above-described existing art.